William wishart



WWI/622107 (Uzi/fay? (Eds/7m? m MW W WISHART FLUID CDMPRESSOR Filed Jan.14. 1926 w a x 6 M m u? a Mm M Z ,the load on 1th .or special' tooling,

Patented Mar. 6,

STATES PATENT OFFICE.

WILLIAM or CLINTON, IowA, ASSIGNOR 'ro NATIONA REFRIGERATIONCORPQBA'IION, or BELOIT, WISCONSIN, A CORPORATION or DELAWARE.

FLUID COMPRESSOR.

Application filed January 14, 1926. Serial No. 81,177.

,My invention 'relates'to fluid compressors. The compressor ofmy presentinvention has particular iitili'ty-"in relatively small or portablerefrigerating systems for domestic ,use, "for examplei H'owever, thepresentinvention is not limited to any particular use orf purpose, butmay be employed wherever found suitable of desirable.

Machines of 'thissort. at present must be made with exact precision. Onediscrepancy may result in improper cooperation between thepartsandimproper operation of the machine. T hisimust be avoided inmakingand machining the parts. Once present, it is practicallyimpossible to cure it. Where wear occurs, renewal becomes necesmy.Special'ftdoling is also usually required and the fmatt'erjof properlubrication presents'a diflicult problem in the presentmachines;*Cousiderable'h nd work is usually requiredtoimalie ,the partstight and to assure p oper ope 'e ibm. t

For the purpose bf permitting the electric driving motorusuall'yemployed to bring the compressor fi oin up to speed, unloaded, machinesof this sort, at present, also require unloadingmeansifor holding one ormore of the valvesunseated, when the apparatus is ,set in ioperation, soas to relieve v "e drivingmea s,

An object my presentinvention is to provide a. generally improvedandsimplified machin that' can be economically produced with standard. topl s a nd withoiit handwork Another pb ject is "to provide a machinewhich oes not require accurate relationing of the, partsfimconstructiona machine in which any inaccuracy maybe convenient- :=1y. taken; in thefirStfas se'mbIy and any wear conveniently taken up as desiredthereafter expeditiously, and without renewal;

Further b hj ects aregtoiniproye the lubri-v at-ion i uds-tqa lim e e.il 4i f, the

u loading i eeshe flhie fi i q i -l qnaint-,th9$e killed nt-the w themanner ot pons tructing and operating the .compresscr of my inyention, Ishall now describ ,jpartienlar of the -eerme tibnewitheaqwmPe Ydrawings, in which Fig. 1 is a sectional view through an embodiment ofthe-invention, taken on the line 11 of Fig. 2;

Fig. 2 is a cross section taken on the line 22 of Fig. 1; L

Fig. 3 is a detail section taken on the line 33 of Fig. 1; and

Fig. 4 is a fragmentary section generally similar to Fig. 2 through amodification.

Referring to the drawings, the particular embodiment of the inventionselected for illustration comprises I an upright vertical external head5 and an internal head member 6 spaced from the head 5 by a ring memberor annulus 8 which defines the compression chamber 9 between the heads 5and 6. Bolts 10 passing through the head 6, ring member 8, and threadedinto the head 5, bind the head member 6 to the head 5 with tple ringmember 8 clamped firmly between t em. I

The drivin shaft 12 has a rotor 13 preferably forme integral therewithand preferably concentric thereon. The rotor 13 is spaced from the innerend of the shaft 12, extending radially from the shaft 12 and operatingbetween the head members 5 and 6 and within the surrounding ring member8. The rotor 13 is preferably of a width sufficiently less than thewidth of the ring member 8 to provide suitable operating clearancebetween the opposite sides of the rotor and the adjacent or opposinginner surfaces of the head members 5 and 6. Just enough clearance toprevent clamping or binding-of the rotor between the head mem- 4connection ternally "or the machine-'may be suitably.

sealed against leakage byfpacking and gland Ineans'18f 1 The head member5 mayjhave an integral pedestalor base 201which maybe-adapted at 21 forbolting upon the slab or'other' support.

The inner end of the shaft 12 and the head member 6, 8 and rotor 13 areall enclosed in a h or cover 25, which preferably holds a body oflubricant 26 about these up to the line H (Fig. 1). The housing may havea charging opening 27 closed by a removable plug 28 and a discharge tube36 leads from the space above the oil level H in the housing 25.

The discharge tube 30 conveys the comthe housing 25 firmly to the headmember 5. The joint between the housing and member 5 is preferablysealed by a suitable gasket 34.

The inlet or admission port with which the inlet line 36 is connected,opens through the head member 5 into an arcuate pocket 38 in theadjacent surface of the ring member 8. The port 35 has a flap 'valve 39which lies within the pocket 38 and may conform generally therewith. Thevalve 39 is secured at one end as by means of a screw 40 to the headmember 5, and its opposite end overlies the port 35 and is free to bedrawn therefrom and to close thereover.

The inner surface 42 of thering 8 is disposed eccentrically around therotor 13 and contacts or engages the periphery of the rotor 13 at 43.The circular interior surface or opening 42 in the ring 8 may beeccentrically disposed with respect to the periphcry 45 of the ring.This makes the ring 8 thicker along the inlet port and pocket to amplyaccommodat the same without unnecessarily increasin the thickness of theentire ring and, at the same time, the eccentric disposal of theinterior of the ring 8 and its contact with the roto'. at 43 may besecured without undue eccentricity ofthe in the h or reservoir 25;

e outlet o the machine cipmprises plsagew M 52 dispose in t e innerhoused end of 12, opening axiall at one end from the inner end of thesha 12 and at its opposite end opening radiallat53throughtherctor 13 byway ofa eeve 54 threaddndially into the rotor. The sleeve 54 has a sat55 for a ball check valve 56 which is free to play between said seat 55and a stop), which may comprise a 'cal wire or pin mounted in the sleeve54. The stop 66 limitsfthe movement of the check valve inwardly, and at'the'limit of its outward v.2 saidcheck valve 56 and closes flse port62.

The compression member or piston element comprises an arm or blade, thewidth of which is substantially equal to the width of'the rotor 13. Atone end the ton element65 has a cylindrical knuckle 68 extending betweenthe head members 5 and 6 and swingably secured in a corresponding socketor recess 69 in the periphery of the rotor 13. The periphery of therotor 13 is scarfed or notched at 70 to form a pocketwhich extendsperipherally from the socket 69 in the direction of rotation of therotor and receives the piston element 65 as it is swung inwardly in therotationof the rotor. The pocket 70 just accommodates the piston element65 at the limit of its inward movement and the piston element in thatposition substantially fills the pocket with its outer peripheryconforming with the periphery of the rotor 13. The are of the out erperiphery of the piston element 65 is substantially the same as thecurvature of the periphery of the rotor 13 so that when the pistonelement is in' the pocket 70, the circular periphery of the rotor willbe uninterrupted.

it should be noted that the openings 72 'in the ring member 8 throughwhich the bolts 10 extend, are larger than the bolts 10.

This permits adjustment of the ring member 8 on the bolts 10 to bringthe ring member into proper contact with the rotor at 43 in the firstassembly and in, spite of variations. adjustment for wear. In the use ofthe device, as the rotor 13 and) ring 8 wear at the point of engagementor contact at 43, due to the rotation of the rotor within the This alsoprovides an expeditious relatively stationary ring, all that isnecessary from time to time, is to unloosen the bolts 10, movev the-ring8 into proper engagement with the rotor to take up any undesirableclearance at the point of contact 43, and to then tighten up the bolts10 to bind the ring 8 firmly in adjusted position.

The compressed fluid is delivered from the outlet 52 to the space 78above the level of the lubricant 26 by a discharge tube 75. This tube isin the form of a stand ipe having an enlarged laterally openingmower end7 6 fitting snugly over the hub or ss 16 and having its upper endextending up above the level of the lubricant 26 and delivering to,

the space 78 from where the com ressed fluid isdischarged or deliveredby t e tube 30.

From the foregoing, it will now be apparent that the eccentricdispositionof the inner surface 42 of the ringB with respect to theperiphery of the rotor 13, forms a generally crescent-shaped compressionchamber 9 between the rotor and r' 8 and of a width corresponding to thedistance between the head members 5 and 6. The contact. 43 may beproperly positioned in theinitial vassembly and maintained as desired bythe adjustability of the ring member 8.

From the foregoing, it will now be apparent that the eccentricdisposition of the inner surface 42'of the ring 8 with respect to theexternal periphery of the rotor 13 forms a crescent-shaped compressionchamber 9, the section or volumetric capacity of which increases fromthe o posite ends to the intermediate part of the c iamber as viewed inFig. 2. The contact or engagement at 43 between the rotor 13 and thesurrounding cylinder ring 8 separates the restricted pressure at 80 fromthe restricted inlet end 82. This contact or engagement 43 is positionedahead of the inlet pocket 38, in the direction of rotation of the rotor13, which is indicated by the arrow .1: in Fig. 2, and thereby closesoil the pressure end 80 and separates it from the inlet pocket 38.

The piston element and all other moving parts are carried by and rotateas a unit with the shaft 12. The concentric disposition of the rotor 13on the shaft 12 balances it thereon, and in starting position the entiremoving system is balanced. As the rotor begins to turn upon starting thecompressor, centrifugal force throws the piston member 65 as it leavesits contact 43 with the cylinder ring 8 out into engagement with theinner surface 42 of the ring 8 and it remains out in engagement with thering 8 in its entire movement through the compression chamber and alsowhen it is forced back into the pocket 70, in which position it forms apart of the periphery of the rotor.

It will be apparent that the compressor is not loaded and does not startcompressing until the speed of the rotor is suflicient to throw thepiston out into compressing engagement with the ring member 8 and thatthis en agement and the com ressing effort is there y at least partiallya unction of the speed of the compressor. Unloading'devices forpermitting the driving motor to bring the compressor -up to speedwithout unduly taxing the motor, which is undesirable, as wellunderstood in the art, are thus avoided. The device is self-unloadingand selfloading. The compressor does not immediately load in'the initialslow rotation of the compressor and not until the compressor comesup tospeed, and then it loads itself.

Any pressure accumulation between the ball check valve 56 and thepiston'member 65, when said piston member is positioned in the pocket70, will also assist in positively throwing the piston member 65 outinto compressing engagement with the ring member 8. This pressureassists in positively opening the piston member 65, and in swinging itout to loaded compressing engagement with the surrounding cylinder ring.

The ball check valve 56 is also thrown out by centrifugal action intoengagement with;

its seat 55, thereby ofi'ering at all times a resistance to thedischarge from the pressure side of the piston element 65. As the pressure in the outlet or discharge line beyond the valve 56 fills up, thatpressure forces the valve 56 firmly upon its seat and positively checksany back flow into the compression chamber.

The rotor and the piston element or compressing member are preferablyformed of hardened steel, although the particular material of these andthe other parts may be varied, as desired.

The operation of the embodiment of the invention shown and described, isas follows Assuming that the inlet 35 is properly connected with thesupply line from which the fluid to be compressed is delivered and thatthe outlet 30 is suitably connected to the line for receiving thecompressed fluid, upon starting the compressor, the shaft 12 and rotor13 turn as a unit and the piston element 65 and other movable parts alsoturn or revolve as a unit therewith.

The compressor remains unloaded until it comes up to speed, whereuponthe centrifugal action holds the piston element 65 out with sufficientforce that it starts to compress the working fluid. As the piston 65leaves the contact point 43 and passes the inlet 38, the valve 39 isdrawn open and the working fluid drawn in throu h the pocket 38 into therestricted end 82 0% the chamber 9 which communicates with the pocket38. The piston 65 moving with the rotor 13 forces the working fluid inthe chamber 9 ahead ofit in its direction of rotation toward theopposite restricted end 80, compressing this working fluid between thepressure end 80 of the chamber 9 and the approaching piston 65 andforcing the compressed fluid out past the valve 56 and through thepassage 52 and outlet 75 through vthe discharge tube 30 to the line orother points to which the compressed fluid is supplied.

As soon as the piston 65 leaves the contactpoint 43 and passes the inlet38, it is positively held open by the pressure ahead of it and thesuction behind it, the space behind the piston being continuouslycharged while the fluid ahead of the piston is continuously compressedin the compressing operation of the machine. As soon as the pistonleaves the contact 43,it is also thrown outwardly by centrifugal action.

The amount of contact between the rotor 13 and the surrounding ring 8may be as desired, and the particular position of this contact in thecycle of operation of the rotor may be adjusted as desired, by looseningthe bolts 10, slipping the ring 8 into the desired position and againtightening the bolts 10.

The balanced system provided is highly rotor-13 and the head member 6. Asecond annular passa 87 between the rotor 13 and the head mem er 5communicates with the passage 86 by means of a longitudinal passage 88through the rotor 13. Leading ongitudinally from the passage 87 is apassage 89 for lubricating the bearing of the shaft 12 irr the headmember 5. 'A passage 90 leading longitudinally in the opposite dimotionfrom the passage 86 supplies lubricant to the bearing of the shaft 12 inthe head member 6.

' From the foregoing, it will now be apparent that the housing 25 formsa reservoir for holding a body of lubricant about the. parts'of themachine. The lubricant is in the high or pressure side, of the machineand it is positively forced the pressure above the surface of its levela r-a in the discharge line, through the passages 85, 86, 87, 88, 89 and90. The body of lubricant effectively seals the parts and the rotatingmember carries the lubricant out and places a lubricant film on thecooperating surfaces of the rotor 13 and head members 5 and 6. Thehibrir.cant also follows up through the compression chamber 9 and: into theinlet 38, placing a lubricant-filmon theinternal. surfaces of thechamber 9 and upon the surfaces of-the rotor 13. The self-feedinglubrication thus provided reduces friction and wear, and the machine isthus self-loading and unloading and self-lubricating.

A assage leading vertically from the annuiar passage 86 extends upthrough the head member 6 and opens above the oil level aa. This.passage forms, in effect, a vent for contaminated lubricant and tends,at least partially, to create a lubricant circula tion between theparts.

- The particular embodiment of the invention described is especiallysuitable for compressing aseous fluids, but the embodiment of its,feaures in a liquid pump is contemplated.

Also, the invention is of course not limited to a single pistoncompressor or pump. A plurality of, pistons 100, 101 and 102 may beemployed with valve passageways 53' leading to the outlet 52' asillustrated in Fig. 4. In this case the rotor is shown as 13', the inletpocket at 38' with'its valve 39 and the lubricant passageway at 88.\Vhere more than one piston is desired, any number or combination ofpistons may be employed.

Ldo not intend to be limited to the precise details shown or described.

I claim 1. In a compressor, the combination of a pair of relativelymovable members spaced peripherally to define a compression chamber andengaging peripherally to form one end of said chamber, and a pistonmember carried by one of said first members and movable with said memberpast the engagement .of said member from one side of said engagement tothe other continuousl in the operation of the compressor, one 0 saidmembers being positively adjustable to vary the point of engagementtherebetween.

2. In a device of the class described, the combination of a rotor, asurrounding cylinder ring spaced from said rotor to form a compressionchamber and cooperating with said rotor to form one end of said chamber,said ring being adjustable in a direction intersecting the periphery ofthe rotor to take up wear and to vary the point of contact between itand the rotor.

In a rotary compressor, an adjustable stationary cylinder ring having anopening,

. a rotor mounted forrotation in said opening,

the inner opening defining surface of said ring being eccentric withrespect to the periphery of the rotor with a compression chamber betweenthem and engaging the periphery of .the rotor to form one of the ends ofsaid compression chamber, and a plurality of p'ston members swingablymounted upon the rotor, said piston members havin wiping contact withthe inner surface of t e stationary ring and movable past the contactbetween the ring and rotor from one side of said contact to the othercontinuously in the operation of the compressor.

4. In combination, a rotor, an adjustable stationary ring membersurrounding the rotorwith its inner surface eccentric with respect tothe periphery of the'rotor and forming a compression chambertherebetween, the inner surface of said ring member having directsurface contact with the periphery of the rotor to form one of the endsof the compression chamber, a piston member swingably mounted upon therotor and having wiping contact with the interior of said ring member,said piston member compressing the contents of the compression chambercircumferentially toward the contact between the rotor and ring memberby the relative rotation therebetween, an inlet to the compressionchamber through the stationarysurrounding ring and an outlet leadingfrom said chamber through the rotor.

5. In a compressor, the combination of a rotor, a stationary cylindricalmember surrounding said rotor, said member being spaced peripherallyfrom the rotor to form a compression chamber therebetween v and havingdirect contact with the periphery of the rotor to form one end of saidcompression chamber and a piston member swingably-mounted upon saidrotor and operable through said chamber past the contact between the clinder member and the rotor from one si e of said contact to the other,said stationary member being capable of positive adjustment to vary thepoint of said contact.

6. In a compressor, the combination of a rotor, a stationar rm membersurrounding the rotor wit its inner surface eccentric with respect-tothe'periphery of themtor and forming a com ression chamber therewith,the inner surface of said rin member having direct surface contact withe periphery of the rotor to form one of the ends of the compressionchamber, and a piston member swingably mounted upon the rotor and havingwiping contact with the interior of the ring member, said piston membercompressing the contents of the compression chamber circumferentially bthe relative rotation between the rotor an ring member, said rin memberhaving means associated therewit for positively adjusting the same tovary the position of the point of contact between said rotor and ring.

In witness whereof, I hereunto subscribe my name this 11th day ofJanuary, 1926.

WILLIAM WISHART.

